On 14/08/16 09:15, charles wrote:
In article , harry
wrote:
On Saturday, 13 August 2016 10:25:36 UTC+1, Fredxxx wrote:
On 13/08/2016 06:55, harry wrote:
On Friday, 12 August 2016 10:24:48 UTC+1, Dave Plowman (News) wrote:
In article ,
Clive George wrote:
Yup. Although the bottle type tended to give a brighter light in
the days when I cycled. But a friction drive is horribly
inefficient.

Sturmey hub vs other bottle? Yes, the sturmey hub wasn't very
powerful - the wheel turns quite slowly, so the magnets required
weren't available (or at least not at a sane price) back then. The
modern hub dynamos give rather more.

That certainly makes sense. Modern low voltage DC motors have also
been improved out of all recognition by better magnets.

There is no such thing as a DC motor. I've told you before.

So what type of voltage do you apply to a "low voltage DC motor"?

It runs on AC. It needs a mechanical inverter to make it run.
https://en.wikipedia.org/wiki/Commutator_(electric)

sitting in front of me on my desk is a small fan which runs directly form
the 5v DC USB supply. There is no mechanical inverter.

Then there is an electronic one


--
Gun Control: The law that ensures that only criminals have guns.

On 14/08/16 13:32, Tim Streater wrote:
In article , Tim Lamb
wrote:

In message ,
harry writes
On Saturday, 13 August 2016 20:22:17 UTC+1, Tim Lamb wrote:
These are expensive and wear out so these days it's replaced with
electronics to turn DC to AC where ever possible.

Hmm.. suppose the commutator is simply switching the current to a
different winding on the armature? Direction of flow may not change
which appears to me to be DC.

The current direction reverses as the commutator segnebt passes under
the brush.

You mean the armature is wound such that the magnetic flux generated
by the winding is reversed?

What's all this about brushes that harry is rabbitting on about. Didn't
think motors had those these days (unlike the cheapies that ran toy
electric trains when I was a nipper).

Some do, some don't.

If they are DC motors and they dont have brushes, they have electronics
doing the same job.


--
Gun Control: The law that ensures that only criminals have guns.

On 14/08/2016 06:16, harry wrote:
On Sunday, 14 August 2016 01:42:30 UTC+1, Fredxxx wrote:
On 13/08/2016 17:56, harry wrote:
On Saturday, 13 August 2016 08:18:46 UTC+1, charles wrote:
In article ,
harry wrote:
On Friday, 12 August 2016 10:24:48 UTC+1, Dave Plowman (News) wrote:
In article ,
Clive George wrote:
Yup. Although the bottle type tended to give a brighter light in the
days when I cycled. But a friction drive is horribly inefficient.

Sturmey hub vs other bottle? Yes, the sturmey hub wasn't very
powerful - the wheel turns quite slowly, so the magnets required
weren't available (or at least not at a sane price) back then. The
modern hub dynamos give rather more.

That certainly makes sense. Modern low voltage DC motors have also been
improved out of all recognition by better magnets.

There is no such thing as a DC motor.
I've told you before.

does that mean that those hand held fans run from a battery need an
inverter to work? I think not. And I'm sure the starter motot in my car
runs on DC.


No it runs on AC.
The "commutator and brushes" are a mechanical inverter.

driven by DC and hence called a DC motor.
https://en.wikipedia.org/wiki/DC_motor

You can deny "A DC motor is any of a class of electrical machines that
converts direct current electrical power into mechanical power" but to
do so only emphasises your ignorance.

These are expensive and wear out so these days it's replaced with electronics to turn DC to AC where ever possible.

Care to give examples of car starter motors that don't use brushes?

They need brushes and a commutator to convert the DC to AC.
Are you so thick you can't Google this?
https://en.wikipedia.org/wiki/Commutator_(electric)

So you are starting to admit that you supply DC to a DC motor.

Or are you the sort to suggest you should supply a DC motor with AC?

On 14/08/2016 06:18, harry wrote:
On Saturday, 13 August 2016 10:25:36 UTC+1, Fredxxx wrote:
On 13/08/2016 06:55, harry wrote:
On Friday, 12 August 2016 10:24:48 UTC+1, Dave Plowman (News) wrote:
In article ,
Clive George wrote:
Yup. Although the bottle type tended to give a brighter light in the
days when I cycled. But a friction drive is horribly inefficient.

Sturmey hub vs other bottle? Yes, the sturmey hub wasn't very powerful -
the wheel turns quite slowly, so the magnets required weren't available
(or at least not at a sane price) back then. The modern hub dynamos give
rather more.

That certainly makes sense. Modern low voltage DC motors have also been
improved out of all recognition by better magnets.

There is no such thing as a DC motor.
I've told you before.

So what type of voltage do you apply to a "low voltage DC motor"?

It runs on AC.

I don't see any transformation of DC to AC I apply to my car starter
motor? In fact all I have is a 12V battery and a switch.

Perhaps you live a sheltered life?

On 14/08/2016 13:53, The Natural Philosopher wrote:
On 14/08/16 09:15, charles wrote:
In article , harry
wrote:
On Saturday, 13 August 2016 10:25:36 UTC+1, Fredxxx wrote:
On 13/08/2016 06:55, harry wrote:
On Friday, 12 August 2016 10:24:48 UTC+1, Dave Plowman (News) wrote:
In article ,
Clive George wrote:
Yup. Although the bottle type tended to give a brighter light in
the days when I cycled. But a friction drive is horribly
inefficient.

Sturmey hub vs other bottle? Yes, the sturmey hub wasn't very
powerful - the wheel turns quite slowly, so the magnets required
weren't available (or at least not at a sane price) back then. The
modern hub dynamos give rather more.

That certainly makes sense. Modern low voltage DC motors have also
been improved out of all recognition by better magnets.

There is no such thing as a DC motor. I've told you before.

So what type of voltage do you apply to a "low voltage DC motor"?

It runs on AC. It needs a mechanical inverter to make it run.
https://en.wikipedia.org/wiki/Commutator_(electric)

sitting in front of me on my desk is a small fan which runs directly form
the 5v DC USB supply. There is no mechanical inverter.

Then there is an electronic one

The synchronous application of voltage to a motor winding is normally
called commutation, and the definition of "inverter" it is the means of
converting DC to AC.

If I should apply an AC current from Harry's inverter to a DC motor,
with a permanent magnet providing the field, I'm sure all you would hear
is a hum.

Nevertheless, I would still apply DC to a DC motor.

On 14/08/2016 06:09, harry wrote:
On Sunday, 14 August 2016 01:34:56 UTC+1, Fredxxx wrote:
On 13/08/2016 18:00, harry wrote:
On Saturday, 13 August 2016 15:21:15 UTC+1, Johnny B Good wrote:
On Sat, 13 Aug 2016 10:49:29 +0100, Syd Rumpo wrote:

In article ,
harry wrote:

There is no such thing as a DC motor.
I've told you before.

Yes there is. You are probably confusing something you read with
reality.

He's obviously oblivious to the concept of the homopolar motor, a true
DC electric motor so well described he-

https://en.wikipedia.org/wiki/Homopolar_motor

--
Johnny B Good

A laboratory device of little/no practical use.
There's one he-
https://www.youtube.com/watch?v=xbCN3EnYfWU
Doesn't it look useful?

I can't believe how ignorant you are, from:
https://en.wikipedia.org/wiki/Homopolar_motor
"B. G. Lamme described in 1912 a homopolar machine rated 2,000 kW, 260
V, 7,700 A and 1,200 rpm with 16 slip rings operating at a peripheral
velocity of 67 m/s. A unipolar generator rated 1,125 kW, 7.5 V 150,000
A, 514 rpm built in 1934 was installed in a U.S. steel mill for pipe
welding purposes."

If you think you can wriggle out of claiming a DC motor isn't a DC
motor, and then claim a unipolar device has no practical use you should
consider seeing your doctor or simply stop spouting your ignorance on
subjects you know nothing about.

1912 Riiiight.
So where are they nowadays?
A dead end invention.

Clearly you are innumerate as well.

Try 1934, and you can find out for yourself how long this generator was
used for.

"Fredxxx" wrote in message
...
There is no such thing as a DC motor.
I've told you before.

So what type of voltage do you apply to a "low voltage DC motor"?

It runs on AC.

I don't see any transformation of DC to AC I apply to my car starter
motor? In fact all I have is a 12V battery and a switch.

Will a motor that is designed to run on DC turn if you connect it to AC? No.
It will buzz and vibrate. Will a motor that is designed to run on AC work if
you feed it DC? No. The rotor will probably give a convulsive jerk and then
stop.

A "DC motor" (one that is designed to run from a DC supply) has a commutator
to energise the various coils in the rotor, in sequence, as the rotor turns
through a stationary magnetic field from a permanent or electro magnet in
the motor casing.

On 14/08/2016 13:54, The Natural Philosopher wrote:
On 14/08/16 13:32, Tim Streater wrote:
In article , Tim Lamb
wrote:

In message ,
harry writes
On Saturday, 13 August 2016 20:22:17 UTC+1, Tim Lamb wrote:
These are expensive and wear out so these days it's replaced with
electronics to turn DC to AC where ever possible.

Hmm.. suppose the commutator is simply switching the current to a
different winding on the armature? Direction of flow may not change
which appears to me to be DC.

The current direction reverses as the commutator segnebt passes under
the brush.

You mean the armature is wound such that the magnetic flux generated
by the winding is reversed?

What's all this about brushes that harry is rabbitting on about. Didn't
think motors had those these days (unlike the cheapies that ran toy
electric trains when I was a nipper).

Some do, some don't.

If they are DC motors and they dont have brushes, they have electronics
doing the same job.

I agree with you, and there is a consensus here that they are still
called DC motors.

On Sunday, 14 August 2016 09:16:35 UTC+1, charles wrote:
In article , harry
wrote:
On Saturday, 13 August 2016 10:25:36 UTC+1, Fredxxx wrote:
On 13/08/2016 06:55, harry wrote:
On Friday, 12 August 2016 10:24:48 UTC+1, Dave Plowman (News) wrote:
In article ,
Clive George wrote:
Yup. Although the bottle type tended to give a brighter light in
the days when I cycled. But a friction drive is horribly
inefficient.

Sturmey hub vs other bottle? Yes, the sturmey hub wasn't very
powerful - the wheel turns quite slowly, so the magnets required
weren't available (or at least not at a sane price) back then. The
modern hub dynamos give rather more.

That certainly makes sense. Modern low voltage DC motors have also
been improved out of all recognition by better magnets.

There is no such thing as a DC motor. I've told you before.

So what type of voltage do you apply to a "low voltage DC motor"?

It runs on AC. It needs a mechanical inverter to make it run.
https://en.wikipedia.org/wiki/Commutator_(electric)

sitting in front of me on my desk is a small fan which runs directly form
the 5v DC USB supply. There is no mechanical inverter.

Then it has an electronic one.
Which takes us right back to the start of the post.
There is an inverter. mechanical or electronic.

On Sunday, 14 August 2016 16:26:58 UTC+1, Fredxxx wrote:
On 14/08/2016 06:16, harry wrote:
On Sunday, 14 August 2016 01:42:30 UTC+1, Fredxxx wrote:
On 13/08/2016 17:56, harry wrote:
On Saturday, 13 August 2016 08:18:46 UTC+1, charles wrote:
In article ,
harry wrote:
On Friday, 12 August 2016 10:24:48 UTC+1, Dave Plowman (News) wrote:
In article ,
Clive George wrote:
Yup. Although the bottle type tended to give a brighter light in the
days when I cycled. But a friction drive is horribly inefficient.

Sturmey hub vs other bottle? Yes, the sturmey hub wasn't very
powerful - the wheel turns quite slowly, so the magnets required
weren't available (or at least not at a sane price) back then. The
modern hub dynamos give rather more.

That certainly makes sense. Modern low voltage DC motors have also been
improved out of all recognition by better magnets.

There is no such thing as a DC motor.
I've told you before.

does that mean that those hand held fans run from a battery need an
inverter to work? I think not. And I'm sure the starter motot in my car
runs on DC.


No it runs on AC.
The "commutator and brushes" are a mechanical inverter.

driven by DC and hence called a DC motor.
https://en.wikipedia.org/wiki/DC_motor

You can deny "A DC motor is any of a class of electrical machines that
converts direct current electrical power into mechanical power" but to
do so only emphasises your ignorance.

These are expensive and wear out so these days it's replaced with electronics to turn DC to AC where ever possible.

Care to give examples of car starter motors that don't use brushes?

They need brushes and a commutator to convert the DC to AC.
Are you so thick you can't Google this?
https://en.wikipedia.org/wiki/Commutator_(electric)

So you are starting to admit that you supply DC to a DC motor.

Or are you the sort to suggest you should supply a DC motor with AC?

Most "DC motors" will run on AC.
Provided the the field magnet is NOT a permanent magnet.
Their other name is a "universal motor"
As found in traditional vacuum cleaners.
(Not modern digital ones which have electronic rectification/invertion.)

https://en.wikipedia.org/wiki/Universal_motor

On 14/08/2016 16:47, NY wrote:
"Fredxxx" wrote in message
...
There is no such thing as a DC motor.
I've told you before.

So what type of voltage do you apply to a "low voltage DC motor"?

It runs on AC.

I don't see any transformation of DC to AC I apply to my car starter
motor? In fact all I have is a 12V battery and a switch.

Will a motor that is designed to run on DC turn if you connect it to AC?
No. It will buzz and vibrate. Will a motor that is designed to run on AC
work if you feed it DC? No. The rotor will probably give a convulsive
jerk and then stop.

A "DC motor" (one that is designed to run from a DC supply) has a
commutator to energise the various coils in the rotor, in sequence, as
the rotor turns through a stationary magnetic field from a permanent or
electro magnet in the motor casing.

The only person here who doesn't agree with that statement is Harry.

On Saturday, 13 August 2016 10:25:36 UTC+1, Fredxxx wrote:
On 13/08/2016 06:55, harry wrote:
On Friday, 12 August 2016 10:24:48 UTC+1, Dave Plowman (News) wrote:
In article ,
Clive George wrote:
Yup. Although the bottle type tended to give a brighter light in the
days when I cycled. But a friction drive is horribly inefficient.

Sturmey hub vs other bottle? Yes, the sturmey hub wasn't very powerful -
the wheel turns quite slowly, so the magnets required weren't available
(or at least not at a sane price) back then. The modern hub dynamos give
rather more.

That certainly makes sense. Modern low voltage DC motors have also been
improved out of all recognition by better magnets.

There is no such thing as a DC motor.
I've told you before.

So what type of voltage do you apply to a "low voltage DC motor"?

He is talking about model aircraft motors which are much better than they once were.

If you want to understand modern high efficiency motors, here's where to start.
All made possible by rare earth magnets.
But these are synchronous motors.

https://en.wikipedia.org/wiki/Synchr..._magnet_motors

You might also look at this.
https://en.wikipedia.org/wiki/Brushl...electric_motor

On 14/08/16 16:28, Fredxxx wrote:
On 14/08/2016 06:18, harry wrote:
On Saturday, 13 August 2016 10:25:36 UTC+1, Fredxxx wrote:
On 13/08/2016 06:55, harry wrote:
On Friday, 12 August 2016 10:24:48 UTC+1, Dave Plowman (News) wrote:
In article ,
Clive George wrote:
Yup. Although the bottle type tended to give a brighter light in the
days when I cycled. But a friction drive is horribly inefficient.

Sturmey hub vs other bottle? Yes, the sturmey hub wasn't very
powerful -
the wheel turns quite slowly, so the magnets required weren't
available
(or at least not at a sane price) back then. The modern hub
dynamos give
rather more.

That certainly makes sense. Modern low voltage DC motors have also
been
improved out of all recognition by better magnets.

There is no such thing as a DC motor.
I've told you before.

So what type of voltage do you apply to a "low voltage DC motor"?

It runs on AC.

I don't see any transformation of DC to AC I apply to my car starter
motor? In fact all I have is a 12V battery and a switch.


Well no you wouldn't. That's what the commutator is - a mechanical inverter.


Perhaps you live a sheltered life?

Perhaps you are ignorant of how an electric motor works....?

--
"The great thing about Glasgow is that if there's a nuclear attack it'll
look exactly the same afterwards."

Billy Connolly

On 14/08/16 16:47, NY wrote:
"Fredxxx" wrote in message
...
There is no such thing as a DC motor.
I've told you before.

So what type of voltage do you apply to a "low voltage DC motor"?

It runs on AC.

I don't see any transformation of DC to AC I apply to my car starter
motor? In fact all I have is a 12V battery and a switch.

Will a motor that is designed to run on DC turn if you connect it to AC?

Some will, yes.


No. It will buzz and vibrate. Will a motor that is designed to run on AC
work if you feed it DC?

Depnds.

No. The rotor will probably give a convulsive
jerk and then stop.

A "DC motor" (one that is designed to run from a DC supply) has a
commutator to energise the various coils in the rotor, in sequence, as
the rotor turns through a stationary magnetic field from a permanent or
electro magnet in the motor casing.

I.e to turn the DC into AC synchronised with the shaft speed.



--
"Anyone who believes that the laws of physics are mere social
conventions is invited to try transgressing those conventions from the
windows of my apartment. (I live on the twenty-first floor.) "

Alan Sokal

On 14/08/16 16:54, Fredxxx wrote:
On 14/08/2016 13:54, The Natural Philosopher wrote:
On 14/08/16 13:32, Tim Streater wrote:
In article , Tim Lamb
wrote:

In message ,
harry writes
On Saturday, 13 August 2016 20:22:17 UTC+1, Tim Lamb wrote:
These are expensive and wear out so these days it's replaced with
electronics to turn DC to AC where ever possible.

Hmm.. suppose the commutator is simply switching the current to a
different winding on the armature? Direction of flow may not change
which appears to me to be DC.

The current direction reverses as the commutator segnebt passes under
the brush.

You mean the armature is wound such that the magnetic flux generated
by the winding is reversed?

What's all this about brushes that harry is rabbitting on about. Didn't
think motors had those these days (unlike the cheapies that ran toy
electric trains when I was a nipper).

Some do, some don't.

If they are DC motors and they dont have brushes, they have electronics
doing the same job.

I agree with you, and there is a consensus here that they are still
called DC motors.

What something is called and what it is, are often wildly different.

I've heard comrade Corbyn referred to as intelligent and compassionate.


--
"Anyone who believes that the laws of physics are mere social
conventions is invited to try transgressing those conventions from the
windows of my apartment. (I live on the twenty-first floor.) "

Alan Sokal

On 14/08/2016 17:50, harry wrote:
On Saturday, 13 August 2016 10:25:36 UTC+1, Fredxxx wrote:
On 13/08/2016 06:55, harry wrote:
On Friday, 12 August 2016 10:24:48 UTC+1, Dave Plowman (News) wrote:
In article ,
Clive George wrote:
Yup. Although the bottle type tended to give a brighter light in the
days when I cycled. But a friction drive is horribly inefficient.

Sturmey hub vs other bottle? Yes, the sturmey hub wasn't very powerful -
the wheel turns quite slowly, so the magnets required weren't available
(or at least not at a sane price) back then. The modern hub dynamos give
rather more.

That certainly makes sense. Modern low voltage DC motors have also been
improved out of all recognition by better magnets.

There is no such thing as a DC motor.
I've told you before.

So what type of voltage do you apply to a "low voltage DC motor"?

He is talking about model aircraft motors which are much better than they once were.

Is it so hard to say "DC"?

In article ,
Fredxxx wrote:
On 14/08/2016 17:50, harry wrote:
On Saturday, 13 August 2016 10:25:36 UTC+1, Fredxxx wrote:
On 13/08/2016 06:55, harry wrote:
On Friday, 12 August 2016 10:24:48 UTC+1, Dave Plowman (News) wrote:
In article ,
Clive George wrote:
Yup. Although the bottle type tended to give a brighter light in
the days when I cycled. But a friction drive is horribly
inefficient.

Sturmey hub vs other bottle? Yes, the sturmey hub wasn't very
powerful - the wheel turns quite slowly, so the magnets required
weren't available (or at least not at a sane price) back then. The
modern hub dynamos give rather more.

That certainly makes sense. Modern low voltage DC motors have also
been improved out of all recognition by better magnets.

There is no such thing as a DC motor. I've told you before.

So what type of voltage do you apply to a "low voltage DC motor"?

He is talking about model aircraft motors which are much better than
they once were.

Is it so hard to say "DC"?

Common to refer to motors as AC, DC, or universal. Except in the likes of
harry's fantasy world.

And just what makes harry think I was referring to model aircraft motors?

--
*If a turtle doesn't have a shell, is he homeless or naked?

Dave Plowman London SW
To e-mail, change noise into sound.

On Sun, 14 Aug 2016 01:34:54 +0100, Fredxxx wrote:

On 13/08/2016 18:00, harry wrote:
On Saturday, 13 August 2016 15:21:15 UTC+1, Johnny B Good wrote:
On Sat, 13 Aug 2016 10:49:29 +0100, Syd Rumpo wrote:

In article ,
harry wrote:

There is no such thing as a DC motor.
I've told you before.

Yes there is. You are probably confusing something you read with
reality.

He's obviously oblivious to the concept of the homopolar motor, a
true
DC electric motor so well described he-

https://en.wikipedia.org/wiki/Homopolar_motor

--
Johnny B Good

A laboratory device of little/no practical use.
There's one he-
https://www.youtube.com/watch?v=xbCN3EnYfWU Doesn't it look useful?

I can't believe how ignorant you are, from:
https://en.wikipedia.org/wiki/Homopolar_motor
"B. G. Lamme described in 1912 a homopolar machine rated 2,000 kW, 260
V, 7,700 A and 1,200 rpm with 16 slip rings operating at a peripheral
velocity of 67 m/s. A unipolar generator rated 1,125 kW, 7.5 V 150,000
A, 514 rpm built in 1934 was installed in a U.S. steel mill for pipe
welding purposes."

If you think you can wriggle out of claiming a DC motor isn't a DC
motor, and then claim a unipolar device has no practical use you should
consider seeing your doctor or simply stop spouting your ignorance on
subjects you know nothing about.

My apologies for not directly responding to Harry's attempt to respond
to my follow up to your post but I have him killfiled so only see his
activity via quotage.

Quite frankly, he didn't deserve responding to since he neglected to
follow that wiki link, preferring to find something else off youtube as
an example to back up his unsubstantiated claim that homopolar motors are
*only* toys with no real world applications.

Quite clearly, you're only wasting your own time by "Confusing him with
Facts" that conflict with his own preconceived ideas. :-)

The only reason why I bothered to 'jump in' was simply to post that
wikipedia link so that anyone in doubt and in danger of accepting Harry's
false assertions as even remotely plausibly true would see these
assertions for what they are, a load of bollix!

--
Johnny B Good

On Sun, 14 Aug 2016 16:54:37 +0100, Fredxxx wrote:

On 14/08/2016 13:54, The Natural Philosopher wrote:
On 14/08/16 13:32, Tim Streater wrote:
In article , Tim Lamb
wrote:

In message ,
harry writes
On Saturday, 13 August 2016 20:22:17 UTC+1, Tim Lamb wrote:
These are expensive and wear out so these days it's replaced with
electronics to turn DC to AC where ever possible.

Hmm.. suppose the commutator is simply switching the current to a
different winding on the armature? Direction of flow may not change
which appears to me to be DC.

The current direction reverses as the commutator segnebt passes
under the brush.

You mean the armature is wound such that the magnetic flux generated
by the winding is reversed?

What's all this about brushes that harry is rabbitting on about.
Didn't think motors had those these days (unlike the cheapies that ran
toy electric trains when I was a nipper).

Some do, some don't.

If they are DC motors and they dont have brushes, they have electronics
doing the same job.

I agree with you, and there is a consensus here that they are still
called DC motors.

Actually, the phrase used is "DC Brushless Motor". In this case, the
motor itself is actually an AC motor but the incorporation of a DC to AC
converter which allows them to be powered from (and *only* from) a DC
voltage supply allows them to be used in place of the classic
mechanically synchronized commutated motor using brush gear (but without
the problems of commutator and brush wear and friction) hence their name,
"Brushless DC Motor".

The homopolar motor is a unique form of true DC motor where only slip
rings are required to energise the rotor without any form of commutation
being required. The major problem is their limitation to very low voltage
high current applications unless you're prepared to design them for
extremely high speeds of rotation on even very low voltage high current
supplies (say a large 2v lead acid accumulator cell or a very large NiCd
or KniFe cell).

--
Johnny B Good

On Sunday, 14 August 2016 22:58:06 UTC+1, Fredxxx wrote:
On 14/08/2016 17:50, harry wrote:
On Saturday, 13 August 2016 10:25:36 UTC+1, Fredxxx wrote:
On 13/08/2016 06:55, harry wrote:
On Friday, 12 August 2016 10:24:48 UTC+1, Dave Plowman (News) wrote:
In article ,
Clive George wrote:
Yup. Although the bottle type tended to give a brighter light in the
days when I cycled. But a friction drive is horribly inefficient.

Sturmey hub vs other bottle? Yes, the sturmey hub wasn't very powerful -
the wheel turns quite slowly, so the magnets required weren't available
(or at least not at a sane price) back then. The modern hub dynamos give
rather more.

That certainly makes sense. Modern low voltage DC motors have also been
improved out of all recognition by better magnets.

There is no such thing as a DC motor.
I've told you before.

So what type of voltage do you apply to a "low voltage DC motor"?

He is talking about model aircraft motors which are much better than they once were.

Is it so hard to say "DC"?

No they are AC motors with an electronic inverter.
There is no commutator these days.

On Sunday, 14 August 2016 17:36:00 UTC+1, Fredxxx wrote:
On 14/08/2016 16:47, NY wrote:
"Fredxxx" wrote in message
...
There is no such thing as a DC motor.
I've told you before.

So what type of voltage do you apply to a "low voltage DC motor"?

It runs on AC.

I don't see any transformation of DC to AC I apply to my car starter
motor? In fact all I have is a 12V battery and a switch.

Will a motor that is designed to run on DC turn if you connect it to AC?
No. It will buzz and vibrate. Will a motor that is designed to run on AC
work if you feed it DC? No. The rotor will probably give a convulsive
jerk and then stop.

A "DC motor" (one that is designed to run from a DC supply) has a
commutator to energise the various coils in the rotor, in sequence, as
the rotor turns through a stationary magnetic field from a permanent or
electro magnet in the motor casing.

The only person here who doesn't agree with that statement is Harry.

The current is reversed as it passes under a brush turning it into AC.

On Monday, 15 August 2016 00:38:49 UTC+1, Dave Plowman (News) wrote:
In article ,
Fredxxx wrote:
On 14/08/2016 17:50, harry wrote:
On Saturday, 13 August 2016 10:25:36 UTC+1, Fredxxx wrote:
On 13/08/2016 06:55, harry wrote:
On Friday, 12 August 2016 10:24:48 UTC+1, Dave Plowman (News) wrote:
In article ,
Clive George wrote:
Yup. Although the bottle type tended to give a brighter light in
the days when I cycled. But a friction drive is horribly
inefficient.

Sturmey hub vs other bottle? Yes, the sturmey hub wasn't very
powerful - the wheel turns quite slowly, so the magnets required
weren't available (or at least not at a sane price) back then. The
modern hub dynamos give rather more.

That certainly makes sense. Modern low voltage DC motors have also
been improved out of all recognition by better magnets.

There is no such thing as a DC motor. I've told you before.

So what type of voltage do you apply to a "low voltage DC motor"?

He is talking about model aircraft motors which are much better than
they once were.

Is it so hard to say "DC"?

Common to refer to motors as AC, DC, or universal. Except in the likes of
harry's fantasy world.

And just what makes harry think I was referring to model aircraft motors?

It was TNP. He is into model aircraft.
As I once was.

On Monday, 15 August 2016 03:31:46 UTC+1, Johnny B Good wrote:
On Sun, 14 Aug 2016 01:34:54 +0100, Fredxxx wrote:

On 13/08/2016 18:00, harry wrote:
On Saturday, 13 August 2016 15:21:15 UTC+1, Johnny B Good wrote:
On Sat, 13 Aug 2016 10:49:29 +0100, Syd Rumpo wrote:

In article ,
harry wrote:

There is no such thing as a DC motor.
I've told you before.

Yes there is. You are probably confusing something you read with
reality.

He's obviously oblivious to the concept of the homopolar motor, a
true
DC electric motor so well described he-

https://en.wikipedia.org/wiki/Homopolar_motor

--
Johnny B Good

A laboratory device of little/no practical use.
There's one he-
https://www.youtube.com/watch?v=xbCN3EnYfWU Doesn't it look useful?

I can't believe how ignorant you are, from:
https://en.wikipedia.org/wiki/Homopolar_motor
"B. G. Lamme described in 1912 a homopolar machine rated 2,000 kW, 260
V, 7,700 A and 1,200 rpm with 16 slip rings operating at a peripheral
velocity of 67 m/s. A unipolar generator rated 1,125 kW, 7.5 V 150,000
A, 514 rpm built in 1934 was installed in a U.S. steel mill for pipe
welding purposes."

If you think you can wriggle out of claiming a DC motor isn't a DC
motor, and then claim a unipolar device has no practical use you should
consider seeing your doctor or simply stop spouting your ignorance on
subjects you know nothing about.

My apologies for not directly responding to Harry's attempt to respond
to my follow up to your post but I have him killfiled so only see his
activity via quotage.

Quite frankly, he didn't deserve responding to since he neglected to
follow that wiki link, preferring to find something else off youtube as
an example to back up his unsubstantiated claim that homopolar motors are
*only* toys with no real world applications.

Quite clearly, you're only wasting your own time by "Confusing him with
Facts" that conflict with his own preconceived ideas. :-)

The only reason why I bothered to 'jump in' was simply to post that
wikipedia link so that anyone in doubt and in danger of accepting Harry's
false assertions as even remotely plausibly true would see these
assertions for what they are, a load of bollix!

Toys are all they are these days. A dead end technology.

On 15/08/2016 06:52, harry wrote:
On Monday, 15 August 2016 03:31:46 UTC+1, Johnny B Good wrote:
On Sun, 14 Aug 2016 01:34:54 +0100, Fredxxx wrote:

On 13/08/2016 18:00, harry wrote:
On Saturday, 13 August 2016 15:21:15 UTC+1, Johnny B Good wrote:
On Sat, 13 Aug 2016 10:49:29 +0100, Syd Rumpo wrote:

In article ,
harry wrote:

There is no such thing as a DC motor.
I've told you before.

Yes there is. You are probably confusing something you read with
reality.

He's obviously oblivious to the concept of the homopolar motor, a
true
DC electric motor so well described he-

https://en.wikipedia.org/wiki/Homopolar_motor

--
Johnny B Good

A laboratory device of little/no practical use.
There's one he-
https://www.youtube.com/watch?v=xbCN3EnYfWU Doesn't it look useful?

I can't believe how ignorant you are, from:
https://en.wikipedia.org/wiki/Homopolar_motor
"B. G. Lamme described in 1912 a homopolar machine rated 2,000 kW, 260
V, 7,700 A and 1,200 rpm with 16 slip rings operating at a peripheral
velocity of 67 m/s. A unipolar generator rated 1,125 kW, 7.5 V 150,000
A, 514 rpm built in 1934 was installed in a U.S. steel mill for pipe
welding purposes."

If you think you can wriggle out of claiming a DC motor isn't a DC
motor, and then claim a unipolar device has no practical use you should
consider seeing your doctor or simply stop spouting your ignorance on
subjects you know nothing about.

My apologies for not directly responding to Harry's attempt to respond
to my follow up to your post but I have him killfiled so only see his
activity via quotage.

Quite frankly, he didn't deserve responding to since he neglected to
follow that wiki link, preferring to find something else off youtube as
an example to back up his unsubstantiated claim that homopolar motors are
*only* toys with no real world applications.

Quite clearly, you're only wasting your own time by "Confusing him with
Facts" that conflict with his own preconceived ideas. :-)

The only reason why I bothered to 'jump in' was simply to post that
wikipedia link so that anyone in doubt and in danger of accepting Harry's
false assertions as even remotely plausibly true would see these
assertions for what they are, a load of bollix!

Toys are all they are these days. A dead end technology.

Do you still apply AC to a DC motor?

And I'm not talking about AC motors or universal motors.

On 15/08/2016 06:45, harry wrote:
On Sunday, 14 August 2016 17:36:00 UTC+1, Fredxxx wrote:
On 14/08/2016 16:47, NY wrote:
"Fredxxx" wrote in message
...
There is no such thing as a DC motor.
I've told you before.

So what type of voltage do you apply to a "low voltage DC motor"?

It runs on AC.

I don't see any transformation of DC to AC I apply to my car starter
motor? In fact all I have is a 12V battery and a switch.

Will a motor that is designed to run on DC turn if you connect it to AC?
No. It will buzz and vibrate. Will a motor that is designed to run on AC
work if you feed it DC? No. The rotor will probably give a convulsive
jerk and then stop.

A "DC motor" (one that is designed to run from a DC supply) has a
commutator to energise the various coils in the rotor, in sequence, as
the rotor turns through a stationary magnetic field from a permanent or
electro magnet in the motor casing.

The only person here who doesn't agree with that statement is Harry.

The current is reversed as it passes under a brush turning it into AC.

Are you now saying that you do apply DC to a DC motor?

On 15/08/2016 06:42, harry wrote:
On Sunday, 14 August 2016 22:58:06 UTC+1, Fredxxx wrote:
On 14/08/2016 17:50, harry wrote:
On Saturday, 13 August 2016 10:25:36 UTC+1, Fredxxx wrote:
On 13/08/2016 06:55, harry wrote:
On Friday, 12 August 2016 10:24:48 UTC+1, Dave Plowman (News) wrote:
In article ,
Clive George wrote:
Yup. Although the bottle type tended to give a brighter light in the
days when I cycled. But a friction drive is horribly inefficient.

Sturmey hub vs other bottle? Yes, the sturmey hub wasn't very powerful -
the wheel turns quite slowly, so the magnets required weren't available
(or at least not at a sane price) back then. The modern hub dynamos give
rather more.

That certainly makes sense. Modern low voltage DC motors have also been
improved out of all recognition by better magnets.

There is no such thing as a DC motor.
I've told you before.

So what type of voltage do you apply to a "low voltage DC motor"?

He is talking about model aircraft motors which are much better than they once were.

Is it so hard to say "DC"?

No they are AC motors with an electronic inverter.
There is no commutator these days.

Do you still deny you apply DC to a DC motor?

On Monday, 15 August 2016 12:29:45 UTC+1, Fredxxx wrote:
On 15/08/2016 06:42, harry wrote:
On Sunday, 14 August 2016 22:58:06 UTC+1, Fredxxx wrote:
On 14/08/2016 17:50, harry wrote:
On Saturday, 13 August 2016 10:25:36 UTC+1, Fredxxx wrote:
On 13/08/2016 06:55, harry wrote:

There is no such thing as a DC motor.
I've told you before.

So what type of voltage do you apply to a "low voltage DC motor"?

He is talking about model aircraft motors which are much better than they once were.

Is it so hard to say "DC"?

No they are AC motors with an electronic inverter.
There is no commutator these days.

Do you still deny you apply DC to a DC motor?

Ignore him, he's on his trolly trip.


NT

On 15/08/16 12:27, Fredxxx wrote:
On 15/08/2016 06:52, harry wrote:
On Monday, 15 August 2016 03:31:46 UTC+1, Johnny B Good wrote:
On Sun, 14 Aug 2016 01:34:54 +0100, Fredxxx wrote:

On 13/08/2016 18:00, harry wrote:
On Saturday, 13 August 2016 15:21:15 UTC+1, Johnny B Good wrote:
On Sat, 13 Aug 2016 10:49:29 +0100, Syd Rumpo wrote:

In article ,
harry wrote:

There is no such thing as a DC motor.
I've told you before.

Yes there is. You are probably confusing something you read with
reality.

He's obviously oblivious to the concept of the homopolar motor, a
true
DC electric motor so well described he-

https://en.wikipedia.org/wiki/Homopolar_motor

--
Johnny B Good

A laboratory device of little/no practical use.
There's one he-
https://www.youtube.com/watch?v=xbCN3EnYfWU Doesn't it look useful?

I can't believe how ignorant you are, from:
https://en.wikipedia.org/wiki/Homopolar_motor
"B. G. Lamme described in 1912 a homopolar machine rated 2,000 kW, 260
V, 7,700 A and 1,200 rpm with 16 slip rings operating at a peripheral
velocity of 67 m/s. A unipolar generator rated 1,125 kW, 7.5 V 150,000
A, 514 rpm built in 1934 was installed in a U.S. steel mill for pipe
welding purposes."

If you think you can wriggle out of claiming a DC motor isn't a DC
motor, and then claim a unipolar device has no practical use you should
consider seeing your doctor or simply stop spouting your ignorance on
subjects you know nothing about.

My apologies for not directly responding to Harry's attempt to respond
to my follow up to your post but I have him killfiled so only see his
activity via quotage.

Quite frankly, he didn't deserve responding to since he neglected to
follow that wiki link, preferring to find something else off youtube as
an example to back up his unsubstantiated claim that homopolar motors
are
*only* toys with no real world applications.

Quite clearly, you're only wasting your own time by "Confusing him with
Facts" that conflict with his own preconceived ideas. :-)

The only reason why I bothered to 'jump in' was simply to post that
wikipedia link so that anyone in doubt and in danger of accepting
Harry's
false assertions as even remotely plausibly true would see these
assertions for what they are, a load of bollix!

Toys are all they are these days. A dead end technology.

Do you still apply AC to a DC motor?

If its a brushless, yes.

And *if* you consider the motor is the far side of the commutator, yes.


And I'm not talking about AC motors or universal motors.

The problem lies in the definition of 'motor' and 'DC motor'.

Is a motor designed ultimately to work on DC, a DC motor, when its
terminals are clearly fed with AC?



--
If you tell a lie big enough and keep repeating it, people will
eventually come to believe it. The lie can be maintained only for such
time as the State can shield the people from the political, economic
and/or military consequences of the lie. It thus becomes vitally
important for the State to use all of its powers to repress dissent, for
the truth is the mortal enemy of the lie, and thus by extension, the
truth is the greatest enemy of the State.

Joseph Goebbels

In article ,
harry scribeth thus
On Sunday, 14 August 2016 17:36:00 UTC+1, Fredxxx wrote:
On 14/08/2016 16:47, NY wrote:
"Fredxxx" wrote in message
...
There is no such thing as a DC motor.
I've told you before.

So what type of voltage do you apply to a "low voltage DC motor"?

It runs on AC.

I don't see any transformation of DC to AC I apply to my car starter
motor? In fact all I have is a 12V battery and a switch.

Will a motor that is designed to run on DC turn if you connect it to AC?
No. It will buzz and vibrate. Will a motor that is designed to run on AC
work if you feed it DC? No. The rotor will probably give a convulsive
jerk and then stop.

A "DC motor" (one that is designed to run from a DC supply) has a
commutator to energise the various coils in the rotor, in sequence, as
the rotor turns through a stationary magnetic field from a permanent or
electro magnet in the motor casing.

The only person here who doesn't agree with that statement is Harry.

The current is reversed as it passes under a brush turning it into AC.

No Harry .. thats switched reversed polarity DC...
--
Tony Sayer

On 15/08/2016 13:20, The Natural Philosopher wrote:
On 15/08/16 12:27, Fredxxx wrote:
On 15/08/2016 06:52, harry wrote:
On Monday, 15 August 2016 03:31:46 UTC+1, Johnny B Good wrote:
On Sun, 14 Aug 2016 01:34:54 +0100, Fredxxx wrote:

On 13/08/2016 18:00, harry wrote:
On Saturday, 13 August 2016 15:21:15 UTC+1, Johnny B Good wrote:
On Sat, 13 Aug 2016 10:49:29 +0100, Syd Rumpo wrote:

In article ,
harry wrote:

There is no such thing as a DC motor.
I've told you before.

Yes there is. You are probably confusing something you read with
reality.

He's obviously oblivious to the concept of the homopolar motor, a
true
DC electric motor so well described he-

https://en.wikipedia.org/wiki/Homopolar_motor

--
Johnny B Good

A laboratory device of little/no practical use.
There's one he-
https://www.youtube.com/watch?v=xbCN3EnYfWU Doesn't it look useful?

I can't believe how ignorant you are, from:
https://en.wikipedia.org/wiki/Homopolar_motor
"B. G. Lamme described in 1912 a homopolar machine rated 2,000 kW, 260
V, 7,700 A and 1,200 rpm with 16 slip rings operating at a peripheral
velocity of 67 m/s. A unipolar generator rated 1,125 kW, 7.5 V 150,000
A, 514 rpm built in 1934 was installed in a U.S. steel mill for pipe
welding purposes."

If you think you can wriggle out of claiming a DC motor isn't a DC
motor, and then claim a unipolar device has no practical use you
should
consider seeing your doctor or simply stop spouting your ignorance on
subjects you know nothing about.

My apologies for not directly responding to Harry's attempt to respond
to my follow up to your post but I have him killfiled so only see his
activity via quotage.

Quite frankly, he didn't deserve responding to since he neglected to
follow that wiki link, preferring to find something else off youtube as
an example to back up his unsubstantiated claim that homopolar motors
are
*only* toys with no real world applications.

Quite clearly, you're only wasting your own time by "Confusing him
with
Facts" that conflict with his own preconceived ideas. :-)

The only reason why I bothered to 'jump in' was simply to post that
wikipedia link so that anyone in doubt and in danger of accepting
Harry's
false assertions as even remotely plausibly true would see these
assertions for what they are, a load of bollix!

Toys are all they are these days. A dead end technology.

Do you still apply AC to a DC motor?

If its a brushless, yes.

And *if* you consider the motor is the far side of the commutator, yes.

So you and harry would apply AC to a DC motor. Sheeez.

I thought you knew better. Yes I know all about commutation, brushed and
brushless, but the significant thing about a DC motor is you apply DC to
it. What happens inside the box isn't helpful.

Next you and harry will be saying that there is no such thing as an
electrically powered motor, they're all magnetic.

In article ,
tony sayer wrote:
The current is reversed as it passes under a brush turning it into AC.

No Harry .. thats switched reversed polarity DC...

Well, yes. AC is generally a sine wave. Be good to see how you achieve
that with a switch. Many inverters make a pretty poor job of producing a
sine wave. ;-)

--
*Life is hard; then you nap

Dave Plowman London SW
To e-mail, change noise into sound.

On 15/08/16 13:50, tony sayer wrote:
thats switched reversed polarity DC...

....otherwise known as 'AC'...


--
"I guess a rattlesnake ain't risponsible fer bein' a rattlesnake, but ah
puts mah heel on um jess the same if'n I catches him around mah chillun".

On Monday, 15 August 2016 14:01:41 UTC+1, Dave Plowman (News) wrote:
In article ,
tony sayer wrote:
The current is reversed as it passes under a brush turning it into AC.

No Harry .. thats switched reversed polarity DC...

Well, yes. AC is generally a sine wave. Be good to see how you achieve
that with a switch. Many inverters make a pretty poor job of producing a
sine wave. ;-)

AC can be any wave form.
Sine/cosine wave forma re associated with rotating electrical machines.
Simple switching gives a square wave.
In a commutator, the point where the sine wave crosses the base line is where the brushes are ituated.
Theoretically.

Changing the load/reversing needs the brushes to be moved ideally.
If they aren't moved excessive arcing occurs which damages the commutator.

On Monday, 15 August 2016 13:58:18 UTC+1, Fredxxx wrote:
On 15/08/2016 13:20, The Natural Philosopher wrote:
On 15/08/16 12:27, Fredxxx wrote:
On 15/08/2016 06:52, harry wrote:
On Monday, 15 August 2016 03:31:46 UTC+1, Johnny B Good wrote:
On Sun, 14 Aug 2016 01:34:54 +0100, Fredxxx wrote:

On 13/08/2016 18:00, harry wrote:
On Saturday, 13 August 2016 15:21:15 UTC+1, Johnny B Good wrote:
On Sat, 13 Aug 2016 10:49:29 +0100, Syd Rumpo wrote:

In article ,
harry wrote:

There is no such thing as a DC motor.
I've told you before.

Yes there is. You are probably confusing something you read with
reality.

He's obviously oblivious to the concept of the homopolar motor, a
true
DC electric motor so well described he-

https://en.wikipedia.org/wiki/Homopolar_motor

--
Johnny B Good

A laboratory device of little/no practical use.
There's one he-
https://www.youtube.com/watch?v=xbCN3EnYfWU Doesn't it look useful?

I can't believe how ignorant you are, from:
https://en.wikipedia.org/wiki/Homopolar_motor
"B. G. Lamme described in 1912 a homopolar machine rated 2,000 kW, 260
V, 7,700 A and 1,200 rpm with 16 slip rings operating at a peripheral
velocity of 67 m/s. A unipolar generator rated 1,125 kW, 7.5 V 150,000
A, 514 rpm built in 1934 was installed in a U.S. steel mill for pipe
welding purposes."

If you think you can wriggle out of claiming a DC motor isn't a DC
motor, and then claim a unipolar device has no practical use you
should
consider seeing your doctor or simply stop spouting your ignorance on
subjects you know nothing about.

My apologies for not directly responding to Harry's attempt to respond
to my follow up to your post but I have him killfiled so only see his
activity via quotage.

Quite frankly, he didn't deserve responding to since he neglected to
follow that wiki link, preferring to find something else off youtube as
an example to back up his unsubstantiated claim that homopolar motors
are
*only* toys with no real world applications.

Quite clearly, you're only wasting your own time by "Confusing him
with
Facts" that conflict with his own preconceived ideas. :-)

The only reason why I bothered to 'jump in' was simply to post that
wikipedia link so that anyone in doubt and in danger of accepting
Harry's
false assertions as even remotely plausibly true would see these
assertions for what they are, a load of bollix!

Toys are all they are these days. A dead end technology.

Do you still apply AC to a DC motor?

If its a brushless, yes.

And *if* you consider the motor is the far side of the commutator, yes.

So you and harry would apply AC to a DC motor. Sheeez.

I thought you knew better. Yes I know all about commutation, brushed and
brushless, but the significant thing about a DC motor is you apply DC to
it. What happens inside the box isn't helpful.

Next you and harry will be saying that there is no such thing as an
electrically powered motor, they're all magnetic.

Quite true. Electricity is convenient way of producing the two magnetic fields neccesary.
Neodymium magnets have replaced electricity for one of the magnetic field in some cases.

On Monday, 15 August 2016 13:58:18 UTC+1, Fredxxx wrote:
On 15/08/2016 13:20, The Natural Philosopher wrote:
On 15/08/16 12:27, Fredxxx wrote:
On 15/08/2016 06:52, harry wrote:
On Monday, 15 August 2016 03:31:46 UTC+1, Johnny B Good wrote:
On Sun, 14 Aug 2016 01:34:54 +0100, Fredxxx wrote:

On 13/08/2016 18:00, harry wrote:
On Saturday, 13 August 2016 15:21:15 UTC+1, Johnny B Good wrote:
On Sat, 13 Aug 2016 10:49:29 +0100, Syd Rumpo wrote:

In article ,
harry wrote:

There is no such thing as a DC motor.
I've told you before.

Yes there is. You are probably confusing something you read with
reality.

He's obviously oblivious to the concept of the homopolar motor, a
true
DC electric motor so well described he-

https://en.wikipedia.org/wiki/Homopolar_motor

--
Johnny B Good

A laboratory device of little/no practical use.
There's one he-
https://www.youtube.com/watch?v=xbCN3EnYfWU Doesn't it look useful?

I can't believe how ignorant you are, from:
https://en.wikipedia.org/wiki/Homopolar_motor
"B. G. Lamme described in 1912 a homopolar machine rated 2,000 kW, 260
V, 7,700 A and 1,200 rpm with 16 slip rings operating at a peripheral
velocity of 67 m/s. A unipolar generator rated 1,125 kW, 7.5 V 150,000
A, 514 rpm built in 1934 was installed in a U.S. steel mill for pipe
welding purposes."

If you think you can wriggle out of claiming a DC motor isn't a DC
motor, and then claim a unipolar device has no practical use you
should
consider seeing your doctor or simply stop spouting your ignorance on
subjects you know nothing about.

My apologies for not directly responding to Harry's attempt to respond
to my follow up to your post but I have him killfiled so only see his
activity via quotage.

Quite frankly, he didn't deserve responding to since he neglected to
follow that wiki link, preferring to find something else off youtube as
an example to back up his unsubstantiated claim that homopolar motors
are
*only* toys with no real world applications.

Quite clearly, you're only wasting your own time by "Confusing him
with
Facts" that conflict with his own preconceived ideas. :-)

The only reason why I bothered to 'jump in' was simply to post that
wikipedia link so that anyone in doubt and in danger of accepting
Harry's
false assertions as even remotely plausibly true would see these
assertions for what they are, a load of bollix!

Toys are all they are these days. A dead end technology.

Do you still apply AC to a DC motor?

If its a brushless, yes.

And *if* you consider the motor is the far side of the commutator, yes.

So you and harry would apply AC to a DC motor. Sheeez.

I thought you knew better. Yes I know all about commutation, brushed and
brushless, but the significant thing about a DC motor is you apply DC to
it. What happens inside the box isn't helpful.

Next you and harry will be saying that there is no such thing as an
electrically powered motor, they're all magnetic.

There ARE such things.
Allegedly.
https://www.youtube.com/watch?v=TwTPwIcSDpg

On 15/08/16 13:58, Fredxxx wrote:
but the significant thing about a DC motor is you apply DC to
it. What happens inside the box isn't helpful.

Well obviously from the comment above you DO NOT know what a brushless
motor is, because if you apply DC to it, it melts.

It needs a controller which is usually externnal to the motor.




Next you and harry will be saying that there is no such thing as an
electrically powered motor, they're all magnetic.

AS I keep saying, its a matter of what you call a motor.

Is this, for example, a DC or an AC motor?

http://www.hobbyking.com/hobbyking/s...ner_Motor.html


Or only 'part of' a motor?


--
Religion is regarded by the common people as true, by the wise as
foolish, and by the rulers as useful.

(Seneca the Younger, 65 AD)

On 15/08/2016 18:20, The Natural Philosopher wrote:
On 15/08/16 13:58, Fredxxx wrote:
but the significant thing about a DC motor is you apply DC to
it. What happens inside the box isn't helpful.

Well obviously from the comment above you DO NOT know what a brushless
motor is, because if you apply DC to it, it melts.

It needs a controller which is usually externnal to the motor.


The last 12V fan was brushless and was designed for 12V DC. There was no
external controller and when I applied 12V DC to it it didn't melt.

Perhaps you should get your brushless DC motors from more reputable
sources that include their own commutation, electronic or otherwise.

You are harry's sock puppet who believes that you should not apply DC to
a DC motor.

On 15/08/2016 17:58, harry wrote:
On Monday, 15 August 2016 14:01:41 UTC+1, Dave Plowman (News) wrote:
In article ,
tony sayer wrote:
The current is reversed as it passes under a brush turning it into AC.

No Harry .. thats switched reversed polarity DC...

Well, yes. AC is generally a sine wave. Be good to see how you achieve
that with a switch. Many inverters make a pretty poor job of producing a
sine wave. ;-)

AC can be any wave form.

Ah, so we are now saying DC is a special case of AC.

The Natural Philosopher wrote:
On 15/08/16 13:58, Fredxxx wrote:
but the significant thing about a DC motor is you apply DC to
it. What happens inside the box isn't helpful.

Well obviously from the comment above you DO NOT know what a brushless
motor is, because if you apply DC to it, it melts.

It needs a controller which is usually externnal to the motor.




Next you and harry will be saying that there is no such thing as an
electrically powered motor, they're all magnetic.

AS I keep saying, its a matter of what you call a motor.

Is this, for example, a DC or an AC motor?

http://www.hobbyking.com/hobbyking/s...ner_Motor.html


Or only 'part of' a motor?



Where does this fit in the scheme of things?

https://youtu.be/i7LOF1GZpdo

Tim

--
Trolls and troll feeders go in my killfile

On 15/08/16 19:22, Fredxxx wrote:
On 15/08/2016 17:58, harry wrote:
On Monday, 15 August 2016 14:01:41 UTC+1, Dave Plowman (News) wrote:
In article ,
tony sayer wrote:
The current is reversed as it passes under a brush turning it into
AC.

No Harry .. thats switched reversed polarity DC...

Well, yes. AC is generally a sine wave. Be good to see how you achieve
that with a switch. Many inverters make a pretty poor job of producing a
sine wave. ;-)

AC can be any wave form.

Ah, so we are now saying DC is a special case of AC.

No. the current and voltage have to reverse to be alternating.

I see your command of English is as poor as your understanding of motor
theory.

--
Microsoft : the best reason to go to Linux that ever existed.